With 3.5 million children living in poverty, and access to social service support very hard to achieve, schools feel “morally bound to do what they can to help”. Photograph: Christopher Thomond

Fiona Gittings, a headteacher in a large primary school in the south of England, is talking about a child whose mother was recently refused asylum. The family was homeless and had been moved from place to place. Finally, they were put in a hostel so far from the school that transport costs were prohibitive. “Being in a hostel was terrifying and utterly unsuitable for the children,” says Gittings. “Carrying on coming to this school, where he was well settled, was so important for that child – it was the only stability he had.”

So Gittings dipped into an emergency fund she has created to pay for a bus pass for both mother and child. She set up the fund a few months ago with £500 of her school budget, £500 from her parent-teacher association and £500 from the church. She knows she can’t continue to pay for their travel though: one adult and one child bus pass for a month comes to about £100. So eventually the child may be forced to move to a new school.

It’s not the first time Gittings has helped poor families out. “This mum had no money – she was literally begging and borrowing to pay for two bus rides across the city to get her child to school. I told her to ask me if she needed help. She’s desperate and she was utterly mortified, but I am so proud that she felt she could come to me.”

But bus passes are the least of it. Gittings lists other recent payments she has made from the emergency fund: new bunks for two children when their beds were destroyed in a domestic violence incident; £12 to a mum heading to court who thought she’d have to pay for a non-molestation order (she brought the money back); a bed, a table and a chair for a boy living with his dad where there was no furniture other than a sofa in the flat. Then there’s £30 to £50 food money every few weeks to a “very proud” grandmother looking after a young boy. “I couldn’t trust the mum not to shove it up her arm, but the nan I could.”

Gittings says she has never been approached for help – “people are really embarrassed” – so she offers support on the basis of what children let slip to staff. “How can it be that people today can’t afford to buy food?” she asks. “A friend came over to look at my school – her kids go to one in another part of the city – and what she couldn’t get over was how much smaller my kids were. I’ve had children tell me they’re hungry. I’ve had children scavenging food. Now I’m giving out actual money; that’s extreme. We deal with the extremes. But I don’t hear about everything. There are families in need I won’t know about.”

It used to be that schools raised money for starving children abroad. Now it appears that they’re having to subsidise hungry kids in their own classrooms. Headteachers in schools across the country say they are spending education money on purely welfare items to ensure that pupils, and their parents, are fed, have sufficient clothes and the facility to wash them, and have enough coins to feed their electricity meters.

Headteachers are not meant to do this. Schools’ funding is split into teaching and learning, and capital budgets – put simply, that’s staff, books and buildings. Pupil premium money – extra funding for disadvantaged pupils – should only be spent to raise attainment and achievement. So schools are skating close to the edge: if a family link worker funded by pupil premium money is advising parents on benefit applications, signposting mum to mental health services, making referrals to food banks, and buying beds for pupils, it is difficult for heads to show these have educational outcomes. Increasingly, they are fulfilling a welfare role.

Eight heads and deputies from primaries and secondaries across the country have told Education Guardian that in the past year they have felt forced to use some of their funding in this way.

“A little boy told me he was fed up with sleeping on the floor at home and I just couldn’t do nothing,” says one. New migrants and their children are vulnerable to homelessness and exploitation, explains another: “One family ended up living in the park. We gave immediate help for accommodation.” Another school has paid for taxis for a pupil to get to hospital appointments. Another has provided clothing, including basics such as underwear. Staff frequently wash and iron pupils’ clothing when that’s not being done at home.

One school is helping to pay for a pupil’s funeral as the family could not afford to bury their child, even after selling their car.

Financial help at Christmas, holidays (as respite for children with chaotic home lives), ovens, washing machines, new baby necessities and sanitary items have all been purchased from school funds. One headteacher bought bikes so two children could get to school.

Paul Henderson, a headteacher in London, says that the children most at risk are often those who don’t quite qualify for free school meals because their parents earn marginally more than the cut-off. “When rent is taken out, they’re more vulnerable than the free-school-meals children. We monitor our list of those who used to be FSM and others who staff have concerns about: we watch the bills for lunch and trips to see how the money comes in.” When dinner money comes in coppers in an envelope, alarm bells ring. “These are little indicators, and we are also very aware of anyone building up arrears.”

Now that so many people work on short-term, part-time or zero-hours contracts, a family can rapidly sink into desperate straits if a parent becomes seriously ill, points out Henderson. “They have no insurance, work doesn’t provide sick pay for any significant period of time, but the outgoings are still there.”

Family link workers report families in difficulty when they visit. “No furniture, no carpets, no heating,” says Gillian Smith, a secondary head. “We had to take a little boy home last week and he stood outside his block of flats and sobbed, asking us not to go inside.”

Things have become noticeably worse in the past couple of years, says Smith. “I’ve got an entire cohort of children who’ve known nothing but the recession,” she says. “Their whole awareness is of excessive poverty. Their levels of poverty have become normalised for them. There’s an acceptance, a finality in the shrug of 15- and 16-year-old girls that the world is one way for some children and another way for them.”

Pupil premium money, on which many of these heads rely to provide free breakfast clubs, uniform, educational trips, school transport and salaries for staff who are effectively working as school-based social workers, is not supposed to be spent in this way, points out Dr Sam Baars at the education thinktank LKMco. “The Department for Education warns against using the pupil premium to fill in for expired social welfare programmes,” he says, “so when it comes to this particular area of school funding, the guidance is explicitly not to spend it on welfare.”

“It comes up time and again,” says Marc Rowland, deputy director at the National Education Trust, and author of A Practical Guide to the Pupil Premium. “From school leaders’ point of view, that money is for some of the most vulnerable ... the DfE’s view is that it should be focused on raising attainment and achievement.”

If a school is spending pupil premium on uniform, Rowland says, it will need to find a way to measure the impact, perhaps by showing that it’s resulted in a child coming to school more often. If a school provides a free breakfast club to incentivise attendance using the pupil premium pot, heads will have to justify that in terms of better results, rather than simply stating that children are hungry and need to be fed.

Heads find ways to stretch the justification for spending pupil premium money – “breaking down barriers to learning” is a phrase often used. “A hungry, worried, unsupported child doesn’t learn, behave or play well,” says one head. But if schools can’t link the spend directly to educational outcomes – and £20 in cash so a family can eat tea this week doesn’t cut it – some heads feel there is no option but to find funds from elsewhere. One, who spends school money on basic needs and also backs a staff fundraising drive that has raised £20,000 in two years, says: “I am fully prepared to justify the use of school funds to ensure our young people have a fully comprehensive education and the basic life experiences every young person should have. However it would be less than ideal to have to make class sizes bigger or make people redundant because of this, hence the staff’s hard work to raise additional funds through the charity.”

These problems are not suddenly going to disappear. The Child Poverty Action Group says that the 3.5 million children already living in poverty will be joined by another 600,000 by 2016, with the total rising to 4.7 million by 2020.

Teaching unions say they are worried at the increasing numbers of reports from members horrified at the situation of the children they are trying to teach. At the Association of School and College Leaders, general secretary Brian Lightman points out that access to social services support, and particularly to mental health services, “is becoming incredibly hard to achieve, and schools will be doing whatever they can to enable disadvantaged students to access the curriculum.”

Headteachers, he observes, must often make very difficult decisions on where to spend their money. If a child can’t access their right to education because of their living conditions, and there is no other support available, “then schools are morally bound to do whatever they can to help.” But, he says, “schools should not have to be a replacement for the welfare state”.